edit: how do you multiquote?? >_< so sorry to ask this....
If you mean a quote within a quote, just reply to the quote within quote. If you mean quote multiple posts, you must just hit the quote button at the bottom right of the posts in question. Go ahead and try it. Just hit the quote button on 2-3 posts, and hit reply. Type what you want, and hit the preview post button. That way you don't have to actually post anything. (Or you could post it, then delete it quickly, which is a cheap way to increase post count. Bu! )
Quoting from multiple pages is a bit more difficult. But once you learn how the code works, you can usually open the different page in a different window, quote it in a reply, and copy/paste, and only actually reply in one post, closing the other out.
:gasp:
EDIT: The edit tool also helps people who need to improve their spelling skills, ie ----> FULANO